View full sizeU.S. Rep. Mo Brooks speaks next to models of SLS rockets after an F-1 Engine gas generator was tested at NASA's Marshall Space Flight Center Thursday, Jan. 24, 2012 in Huntsville, Ala. The test, with parts taken from an engine intended to fly in the Apollo program, is being studied my Marshall engineers in developing the next generation of rocket engines for NASA's Space Launch System (SLS). (Eric Schultz / eschultz@al.com)

WASHINGTON - The House panel overseeing NASA has endorsed funding for the big new rocket being developed in Huntsville, Alabama, but it isn't unanimous. Among the dissenters is the committee's vice-chairman, who thinks the Space Launch System is unaffordable.

U.S. Rep. Lamar Smith, R-Texas, the chairman of the House Committee on Science, Space and Technology, submitted the committee's views on NASA's 2014 budget to House Budget Committee Chairman Paul Ryan on March 1. Read the full letter below. President Obama has not released his request for NASA in 2014 yet.

Smith noted that NASA is currently pursuing two tracks to get American astronauts back into space aboard American spacecraft. The first is the agency's commercial space program to fund companies such as SpaceX, Boeing and Sierra Nevada as they develop rockets capable of carrying astronauts to and from the International Space Station. The second is the Space Launch System, which is being developed in Huntsville as an evolvable system leading to a rocket big enough to carry astronauts to deep-space destinations such as Mars.

"While NASA's Commercial Crew program could be the primary means of transporting American astronauts," Smith wrote Ryan, "we cannot be solely reliant on this program. The Orion MPCV (Multi-purpose Crew Vehicle), Space Launch System, and Commercial Crew programs require a program track with a sufficient budget to support the space station as soon as possible in preparation for the next steps of human exploration beyond Low Earth Orbit ..."

Smith went on to say that "due to a constrained budget environment, goals - such as maintaining 2.5 commercial teams or demonstration flights beyond low-Earth Orbit - need to be secondary to the primary goal of developing a vehicle to safely transport American astronauts to the International Space Station and beyond." The only entity planning a demonstration flight beyond LEO now is NASA, which plans to launch an uncrewed SLS mission around the moon in 2017.

Smith said the committee supported NASA's budget request of $17.7 billion for 2013 before sequestration. But Smith said NASA under the Obama Administration shows a "lack of leadership in space exploration, both human and robotic" and is ceding America's leadership in space to fund "environmental-monitoring satellites and studies."

Smith also said NASA's Earth Science budget request for 2013 was $300 million more than the agency spent before President Obama took office, while the planetary science budget was $300 million less in 2013.

Among the committee members signing the letter was U.S. Rep. Mo Brooks (R-Huntsville).

Committee vice-chairman, Rep. Dana Rohrabacher ( R-Ca.), released his own statement March 8 saying that, while he agreed with much of the committee's views and budget estimates, "there is one specific area on which I wish to state a different view, as I have done for the past few years."

Rohrabacher believes Commercial Crew is America's "most critical near-term civil space goal" and funding for it should be increased. "SLS is unaffordable" Rohrabacher continued," and with relatively modest expenditures on specific technology development, we do not need a heavy lift vehicle of that class to explore the Moon, Mars, or near-Earth asteroids."

Rohrabacher was also skeptical of NASA's Earth Science programs. "These programs should not be located at NASA," he wrote, "whose core and unique mission is exploring space."

(This post was updated March 11, 2013 at 3:50 CDT to correct the date of NASA's planned uncrewed flight around the moon with its Space Launch System.)